Whenever I render, it doesn't show the texture
Assuming your texture is an image file this should work.

Change it from Blender Render to Cycles Render. Go into edit mode(tab-key) and unwrap it(u-key). Go into the node editor. In the node editor bring up the node add menu (shift + a), and select image texture. Assign your image/texture to the image texture box. Attach the yellow node from the texture image box to the diffuse box.. This should work.